Bowels: obstruction, IBS and IBD

Symptoms: nausea vomiting: early in high-level obstruction. Faeculent vomiting is due to retrograde peristalsis and is limited to low obstruction dysphagia abdominal pain: Diffuse, central abdominal pain of a colicky nature. Pain is less or absent in paralytic ileus Constipation: early in low obstruction and late in high-level obstruction Severe pain and tenderness suggest ischaemia or perforation. Clinical signs: abdominal distention: the lower the level of obstruction, the more marked tympany due to an air-filled stomach high-pitched bowel sounds

CAUSESSmall intestinal obstruction:May be due to adhesions, strangulated hernia, malignancy or volvulus. The majority (75%) of small bowel obstructions are attributed to intra-abdominal adhesions from prior operations.Large intestinal obstruction: Is most often the result of colorectal malignancies. Patients are often aged over 70. The risk of obstruction increases the further down the bowel the lesion is sited, as the contents become more solid. Sigmoid and caecal volvulus: The sigmoid colon is the most common site of volvulus and accounts for 5% of large bowel obstruction. It is usually seen in the elderly or those with psychiatric illness. It is the most common cause of intestinal obstruction in Africa and Asia (x10 incidence) Congenital gastrointestinal malformations can cause neonatal intestinal obstruction. Another cause of meconium ileus is cystic fibrosis.Hirschsprung's disease can cause blockage of the bowel. It may present early or late in childhood. Intussusception in children blocks the bowel. Intussusception in adults is much less common and does not tend to obstructMiscellaneous causes in adults include gallstone ileus (which occurs when a large gallstone is passed into the gut and blocks it), severe constipation causing faecal impaction and Crohn's disease. Malignancy may cause obstruction from outside the gut - eg, gynaecological tumours. Paralytic ileus describes the condition in which the bowel ceases to function and there is no peristalsis. It results from massive dilatation of the colon but possibly small intestine too. It may occur in association with a number of medical conditions including: Chest infection Acute myocardial infarction Stroke Acute kidney injury Puerperium Trauma Severe hypothyroidism Electrolyte disturbance Diabetic ketoacidosis Postoperative ileus is a significant problem. Reduced handling of the bowel at operation is recommended.

Complications: ischaemia of the bowel (necrosis) peritonitis (perforation) septicaemia Fluid and electrolyte imbalance hypovolaemia and circulatory collapse  acute kidney injury

Investigations:Fluid charts are required to monitor intake and output (oliguria is an important sign of early dehydration.)Plain abdominal X-ray : obstruction of the small bowel shows ladder-like series of small bowel loops but this also occurs with an obstruction of the proximal colon. Fluid levels in the bowel can be seen in upright views. Distended loops may be absent if obstruction is at the upper jejunum. The colon is in the more peripheral part of the film and distension may be very marked. Fluid levels will also be seen in paralytic ileus and the small bowel is distended throughout its length. In an erect film a fluid level in the stomach is normal as may be a level in the caecum. Multiple fluid levels and distension of the bowel are abnormal.  Gas under the diaphragm suggests perforation. Blood should be taken for FBC, U&Es and creatinine  water-soluble contrast enema X-ray may be helpful CT, MRI and US scan

NICE Guidelines:Patients must give at least a 6-month history of either: Abdominal pain or discomfort. Bloating. Change in bowel habit. Consider positively diagnosing IBS only if abdominal pain is either relieved by defecation, or associated with altered bowel frequency or stool form; AND at least 2 of the following are present: Altered passage of stool (straining, urgency, incomplete evacuation). Abdominal bloating (women >men), distention tension or hardness. Symptoms aggravated by eating. Passage of mucus rectally. Lethargy, nausea, backache and bladder symptoms may be used to support diagnosis.

Crohn's Disease: characterised by focal, asymmetrical, transmural and occasionally granulomatous inflammation It may affect any part of the gastrointestinal tract but particularly the terminal ileum and proximal colon. Disease is restricted to the small bowel in 30% of patients and the large bowel in 30% of patients. 40% of patients have involvement of the small and large bowel. Fistulae and strictures may occur. Unlike ulcerative colitis, there may be unaffected bowel between areas of active disease (skip lesions). The clinical course is characterised by exacerbations and remission. peak age: 15-30, and 60-80 y/o female:male ratio in adults is 1.8:1 (reversed in kids) smoking increases risk Symptoms: diarrhoea (which may be bloody and become chronic - ie present for more than six weeks), abdominal pain and/or weight loss.  periods of acute exacerbation, interspersed with remissions or less active disease. Systemic symptoms of malaise, anorexia, or fever are common. Extra-intestinal manifestations: Clubbing, erythema nodosum, pyoderma gangrenosum. mouth ulcers, perianal (abscess, skin tags, fistulaes) or anal fissure. Conjunctivitis, episcleritis, iritis. Large joint arthritis, sacroiliitis (10-12%), ankylosing spondylitis. Fatty liver, primary sclerosing cholangitis (rare), cholangiocarcinoma (rare). Granulomata may occur (in 50-70% of patients) in the skin, epiglottis, mouth, vocal cords, liver, nodes, mesentery, peritoneum, bones, joints, muscle or kidney. Renal stones. Osteomalacia. Malnutrition. Amyloidosis. Children may present with poor growth, delayed puberty, malnutrition and bone demineralisation.

Ulcerative colitis (UC): most common IBD, total colonectomy is curative autoimmune condition triggered by colonic bacteria causing inflammation in the gastrointestinal tract (only colon and rectum) lesions are CONTINUOUS in nature Distal disease (left-sided colitis): colitis confined to the rectum (proctitis) or rectum and sigmoid colon (proctosigmoiditis). More extensive disease includes: left-sided colitis (up to the splenic flexure, 40% of patients), extensive colitis (up to the hepatic flexure) and pancolitis (affecting the whole colon, 20% of patients). Some patients with pancolitis may have involvement of the terminal ileum due to an incompetent ileocaecal valve. A family history is present in around 25-40% of children; siblings of an individual with Crohn's disease are 17-35 times more likely than the general population to develop the condition. The risk of IBD is increased in women using oral contraceptives but the absolute increase in risk is very low. The risk of ulcerative colitis is decreased in smokers. peak incidence is between the ages of 15 and 25 years, with a second, smaller peak between 55 and 65 years. Symptoms: The cardinal symptom is bloody diarrhoea. colicky abdominal pain, urgency, or tenesmus (a feeling of incomplete defecation with an inability or difficulty to empty the bowel at defecation). Disease limited to the rectum (proctitis) may present with constipation and rectal bleeding. Systemic upset, including malaise, fever, weight loss  Extra-intestinal symptoms: Erythema nodosum. Aphthous ulcers. Episcleritis. large joints arthropathy (eg, the wrists, hips, knees). Usually related to activity of colitis: Pyoderma gangrenosum. Anterior uveitis. Not related to activity of colitis: Sacroiliitis. Ankylosing spondylitis. Primary sclerosing cholangitis.

Investigations FBC, CRP, U&Es, LFTs, stool culture and microscopy. High CRP levels are indicative of active disease or a bacterial complication. Low magnesium and serum albumin levels are sometimes found in ulcerative colitis. Stool culture, including ova, cysts and parasites and also Clostridium difficile toxin  anti-S. cerevisiae antibodies (ASCA)) are more common in Crohn's disease  Perinuclear antineutrophil cytoplasmic antibody (p-ANCA), is more common in ulcerative colitis  Colonoscopy (inc sigmoid and rectum) and biopsies  small bowel follow-through or small bowel enema  abdominal X-ray, ultrasound, CT and MRI scanning Pelvic MRI for perianal disease

Intestinal obstruction

IBS

ibd